 /*
  * $Header: /cvshome/build/org.osgi.framework/src/org/osgi/framework/Filter.java,v 1.16 2007/02/21 16:49:05 hargrave Exp $
  *
  * Copyright (c) OSGi Alliance (2000, 2007). All Rights Reserved.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
  * http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
 package org.osgi.framework;

 import java.util.Dictionary ;

 /**
  * An RFC 1960-based Filter.
  * <p>
  * <code>Filter</code> objects can be created by calling
  * {@link BundleContext#createFilter} with the chosen filter string.
  * <p>
  * A <code>Filter</code> object can be used numerous times to determine if the
  * match argument matches the filter string that was used to create the
  * <code>Filter</code> object.
  * <p>
  * Some examples of LDAP filters are:
  *
  * <pre>
  * &quot;(cn=Babs Jensen)&quot;
  * &quot;(!(cn=Tim Howes))&quot;
  * &quot;(&amp;(&quot; + Constants.OBJECTCLASS + &quot;=Person)(|(sn=Jensen)(cn=Babs J*)))&quot;
  * &quot;(o=univ*of*mich*)&quot;
  * </pre>
  *
  * @since 1.1
  * @see "Core Specification, section 5.5, for a description of the filter string
  * syntax."
  * @ThreadSafe
  * @version $Revision: 1.16 $
  */
 public interface Filter {
     /**
      * Filter using a service's properties.
      * <p>
      * The filter is executed using the keys and values of the referenced
      * service's properties. The keys are case insensitively matched with the
      * filter.
      *
      * @param reference The reference to the service whose properties are used
      * in the match.
      *
      * @return <code>true</code> if the service's properties match this
      * filter; <code>false</code> otherwise.
      */
     public boolean match(ServiceReference reference);

     /**
      * Filter using a <code>Dictionary</code> object. The Filter is executed
      * using the <code>Dictionary</code> object's keys and values. The keys
      * are case insensitively matched with the filter.
      *
      * @param dictionary The <code>Dictionary</code> object whose keys are
      * used in the match.
      *
      * @return <code>true</code> if the <code>Dictionary</code> object's
      * keys and values match this filter; <code>false</code>
      * otherwise.
      *
      * @throws IllegalArgumentException If <code>dictionary</code> contains
      * case variants of the same key name.
      */
     public boolean match(Dictionary dictionary);

     /**
      * Returns this <code>Filter</code> object's filter string.
      * <p>
      * The filter string is normalized by removing whitespace which does not
      * affect the meaning of the filter.
      *
      * @return Filter string.
      */
     public String toString();

     /**
      * Compares this <code>Filter</code> object to another object.
      *
      * @param obj The object to compare against this <code>Filter</code>
      * object.
      *
      * @return If the other object is a <code>Filter</code> object, then
      * returns <code>this.toString().equals(obj.toString()</code>;<code>false</code>
      * otherwise.
      */
     public boolean equals(Object obj);

     /**
      * Returns the hashCode for this <code>Filter</code> object.
      *
      * @return The hashCode of the filter string; that is,
      * <code>this.toString().hashCode()</code>.
      */
     public int hashCode();

     /**
      * Filter with case sensitivity using a <code>Dictionary</code> object.
      * The Filter is executed using the <code>Dictionary</code> object's keys
      * and values. The keys are case sensitively matched with the filter.
      *
      * @param dictionary The <code>Dictionary</code> object whose keys are
      * used in the match.
      *
      * @return <code>true</code> if the <code>Dictionary</code> object's
      * keys and values match this filter; <code>false</code>
      * otherwise.
      *
      * @since 1.3
      */
     public boolean matchCase(Dictionary dictionary);
 }

